Display device and electronic device

ABSTRACT

A display device includes a circuit layer including: a plurality of transistors; a plurality of metal layers; and a plurality of wirings. The display device includes a display layer including first, second and third light emitting elements. The first light emitting element includes a first anode electrode and a first light emitting layer, a surface of the first anode electrode having a first surface contour structure; the second light emitting element includes a second anode electrode and a second light emitting layer, a surface of the second anode electrode having a second surface contour structure which is different from the first surface contour structure; and the third light emitting element includes a third anode electrode and a third light emitting layer, a surface of the third anode electrode having a third surface contour structure which is different from the second surface contour structure.

CROSS REFERENCES TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 13/155,027, filed Jun. 7, 2011, which applicationclaims priority to Japanese Patent Application No. JP 2010-137260, filedin the Japanese Patent Office on Jun. 16, 2010, the entire contents ofwhich is being incorporated herein by reference.

BACKGROUND

In recent years, as display devices replacing liquid crystal displays,organic EL displays using self-luminous organic light emitting elementshave been put into practical use. The organic EL displays are ofself-luminous type, and thus have a wide viewing angle as compared withliquid crystal displays or the like and sufficient responsiveness tohigh definition and high speed video signals.

Regarding the light emitting elements hitherto, a trial has been carriedout to improve display performance by controlling light emitted fromemission layers, for example, by improving chromatic purity of emissioncolors or luminous efficiency through introducing a resonator structure(for example, see International Publication No. 01/39554). For example,as shown in FIG. 13, in an organic light emitting element of a topemission type where light is emitted from a surface (upper surface)opposite to a substrate, a light emitting portion Z10 has a structurewhere an anode electrode Z13, a organic layer Z14, and a cathodeelectrode Z16 are sequentially laminated via a driving transistor ZTr1,and light is multiply reflected from the organic layer Z14 between theanode electrode Z13 and the cathode electrode Z16. Here, the drivingtransistor ZTr1 drives the light emitting portion Z10 and constitutes apixel driving circuit along with a signal line Z120A or the like. Inaddition, in FIG. 13, the reference numeral Z111 denotes a substrate,the reference numeral Z212 denotes a gate insulation layer of thedriving transistor ZTr1, the reference numeral Z217 denotes a protectivelayer made of silicon nitride or the like, and the reference numeralZ218 denotes a planarization layer made of polyimide or the like. Also,the reference numeral Z17 denotes a metal layer which is an auxiliaryline, the reference numeral Z24 denotes an aperture defining insulationlayer, the reference numeral Z18 is a protective layer made of siliconnitride or the like, and the reference numeral Z19 denotes a sealingsubstrate made of a transparent material.

In addition, in a typical organic EL display, as shown in FIG. 13, theorganic light emitting element Z10 has a sterical shape with concave andconvex in the laminated direction in the emission region, not aplanarized shape. For this reason, if the external light L_(IN) isincident on the light emitting portion Z10, the reflected light L_(R)other than specular light causes diffraction phenomenon, and thus aviewer may see unwanted rainbow colored light according to positions ofthe viewer. There is a problem in that this unnecessary rainbow coloredlight interferes within the organic light emitting elements in a pixelor within adjacent pixels and may be strengthened at a specific angle.

Specifically, the intensity of the reflected light L_(R) may increase ifsatisfying the following conditional equation (1), and the intensity ofthe reflected light L_(R) may decrease if satisfying the followingconditional equation (2). Here, m is an integer value, λ is awavelength, P is a pitch of arranged pixels, and θ is an angle of thereflected light L_(R) with respect to the specular light.

m·λ=P·sin θ  (1)

(m+½)·λ=P·sin θ  (2)

The occurrence of the interference greatly hinders the viewer fromrecognizing the originally displayed image.

This sterical shape is caused by the existence of lines such as thesignal line Z120A in addition to the driving transistor ZTr1, which arepositioned in the lower layer of the light emitting portion Z10.Therefore, if the protective layer Z217 or the planarization layer Z218covering the pixel driving circuit is made sufficiently thick, the uppersurface of the planarization layer Z218 on which the light emittingportion Z10 is formed and thus a planarized surface with high accuracycan be obtained. Therefore, the planarity of the light emitting portionZ10 is naturally improved. However, in that case, the thickness of theentire device increases, and thus there is a problem in that theintrinsic advantage of the organic EL display which is thinner than theliquid crystal display and the like may not be utilized.

It is desirable to provide a display device which is thin and canachieve better image display performance.

SUMMARY

The present disclosure relates to a display device provided withself-luminous light emitting elements including organic layers.

In one example embodiment, a display device for suppressing reflectedlight includes a driving circuit and a display region. In one exampleembodiment, the display region includes a plurality of pixels whichincludes a first pixel. In one example embodiment, the first pixel has afirst light emitting element which includes a first light emittingportion having a first layer surface. In one example embodiment, thefirst pixel has a second light emitting element which includes a secondlight emitting portion having a second, different layer surface. In oneexample embodiment, the first pixel has a third light emitting elementwhich includes a third light emitting portion having a third, differentlayer surface.

In one example embodiment, the first light emitting element includes afirst thin film transistor structure, the second light emitting elementincludes a second, different thin film transistor structure, and thethird light emitting element includes a third, different thin filmtransistor structure. In one example embodiment, each of the layersurfaces of each of the light emitting elements is different from eachother based on each of the different, thin file transistor structures.

In one example embodiment, the first light emitting element includes afirst metal layer, the second light emitting element includes a second,different metal layer, and the third light emitting element includes athird, different metal layer. In one example embodiment, each of thelayer surfaces of each of the light emitting elements is different fromeach other based on each of the different, metal layers.

In one example embodiment, the plurality of pixels includes a secondpixel located horizontally adjacent to the first pixel. In one exampleembodiment, the second pixel has a fourth light emitting element whichincludes a fourth light emitting portion having a fourth, differentlayer surface. In one example embodiment, the second pixel has a fifthlight emitting element which includes a fifth light emitting portionhaving a fifth, different layer surface. In one example embodiment, thesecond pixel has a sixth light emitting element which includes a sixthlight emitting portion having a sixth, different layer surface. In oneexample embodiment, each of the layer surfaces is horizontally adjacentto each other.

In one example embodiment, the lighting elements of the first pixel andthe lighting elements of the second pixel are arranged in a constantorder in a first direction.

In one example embodiment, the display device includes: (a) a firstdriving circuit having a first driving element configured to drive thefirst light emitting element, wherein a first electrode having a firstplanar shape forms the first driving element; (b) a second drivingcircuit having a second driving element configured to drive the secondlight emitting element, wherein a second electrode having a secondplanar shape forms the second driving element; (c) a third drivingcircuit having a third driving element configured to drive the thirdlight emitting element, wherein a third electrode having a third planarshape forms the third driving element; (d) a fourth driving circuithaving a fourth driving element configured to drive the fourth lightemitting element, wherein a fourth electrode having a fourth planarshape forms the fourth driving element, the fourth electrode having adifferent undulating layer surface from the first electrode; (e) a fifthdriving circuit having a fifth driving element configured to drive thefifth light emitting element, wherein a fifth electrode having a fifthplanar shape forms the fifth driving element, the fifth electrode havinga different undulating layer surface from the second electrode; and (f)a sixth driving circuit having a sixth driving element configured todrive the sixth light emitting element, wherein a sixth electrode havinga sixth planar shape forms the sixth driving element, the sixthelectrode having a different undulating layer surface from the thirdelectrode.

In one example embodiment, each of the lighting emitting elements aredifferent from each other.

In one example embodiment, the first light emitting element includes:(i) a first electrode layer; (ii) a first organic layer which includes afirst emission layer; and (iii) a second electrode layer. In one exampleembodiment, the second light emitting element includes: (i) a thirdelectrode layer; (ii) a second organic layer which includes a secondemission layer; and (iii) a fourth electrode layer. In one exampleembodiment, the third light emitting element includes: (i) a fifthelectrode layer; (ii) a third organic layer which includes a thirdemission layer; and (iii) a sixth electrode layer.

In one example embodiment, the plurality of pixels are arranged in afirst direction at a first period and arranged in a second direction ata second period, the first direction crossing the second direction, thesecond period being longer than the first period.

In one example embodiment, the display device includes: (a) a firstdriving circuit having a first driving element configured to drive thefirst light emitting element, wherein a first electrode having a firstplanar shape forms the first driving element; (b) a second drivingcircuit having a second driving element configured to drive the secondlight emitting element, wherein a second electrode having a second,different planar shape forms the second driving element; and (c) a thirddriving circuit having a third driving element configured to drive thethird light emitting element, wherein a third electrode having a third,different planar shape forms the third driving element.

In one example embodiment, the plurality of pixels are arranged in afirst direction and arranged in a second, different direction. In oneexample embodiment, the plurality of pixels include a plurality of lightemitting elements having undulation of the same layer surface shapewhich are arranged at an irregular interval in at least one of the firstdirection and the second direction.

In one example embodiment, a method of manufacturing a display deviceincludes, for a pixel, forming, on a substrate: (a) a first lightemitting element which includes a first light emitting portion having afirst layer surface; (b) a second light emitting element which includesa second light emitting portion having a second, different layersurface; and (c) a third light emitting element which includes a thirdlight emitting portion having a third, different layer surface.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram illustrating a configuration of a display deviceaccording to an example embodiment of the present disclosure.

FIG. 2 is a diagram illustrating an example of a pixel driving circuitshown in FIG. 1.

FIG. 3 is a plan view illustrating a configuration of the display regionshown in FIG. 1.

FIG. 4 is a cross-sectional view illustrating a first light emittingportion in the display region shown in FIG. 1.

FIG. 5 is a cross-sectional view illustrating a second light emittingportion in the display region shown in FIG. 1.

FIG. 6 is a cross-sectional view illustrating a third light emittingportion in the display region shown in FIG. 1.

FIGS. 7A, 7B, and 7C are plan views illustrating a configuration of thepixel driving circuit forming layer shown in FIGS. 4 to 6.

FIG. 8 is an enlarged cross-sectional view illustrating the organiclayer shown in FIGS. 4 to 6.

FIG. 9 is an enlarged cross-sectional view illustrating a cross-sectionof the connection portion shown in FIG. 3.

FIGS. 10A, 10B, and 10C are plan views illustrating a configuration of apixel driving circuit forming layer according to a first modifiedexample.

FIGS. 11A, 11B, and 11C are plan views illustrating a configuration of apixel driving circuit forming layer according to a second modifiedexample.

FIGS. 12A, 12B, and 12C are plan views illustrating a configuration of apixel driving circuit forming layer according to a third modifiedexample.

FIG. 13 is a cross-sectional view illustrating a configuration of adisplay device in the related art.

DETAILED DESCRIPTION

Hereinafter, example embodiments of the present disclosure will bedescribed with reference to the accompanying drawings.

FIG. 1 shows a configuration of a display device using light emittingelements according to an example embodiment of the present disclosure.The display device may be used as a very thin organic light emittingcolor display device and the like. This display device includes adisplay region 110 on a substrate 111. Around the display region 110 onthe substrate 111, for example, a signal driving circuit 120, a scanningline driving circuit 130, and a power supply line driving circuit 140are formed.

In the display region 110, organic light emitting elements 1R, 1G and 1B(not shown in FIG. 1) including light emitting portions 10 (10R, 10G,10B), and pixel driving circuits 150 for driving the portions areformed. In the pixel driving circuits 150, a plurality of signal lines120A (120A1, 120A2, . . . , 120Am, . . . ) is disposed in the columndirection (Y direction), and a plurality of scanning lines 130A (130A1,. . . , 130An, . . . ) and a plurality of power supply lines 140A(140A1, . . . , 140An, . . . ) are disposed in the row direction (Xdirection). One of the light emitting portions 10R, 10G and 10B isprovided at each of the intersections of the signal lines 120A and thescanning lines 130A. The respective signal lines 120A are connected tothe signal driving circuit 120, the respective scanning lines 130A areconnected to the scanning line driving circuit 130, and the respectivepower supply lines 140A are connected to the power supply line drivingcircuit 140.

The signal driving circuit 120 supplies signal voltages of image signalscorresponding to luminance information supplied from a signal supplysource (not shown), to the respective selected light emitting portions10R, 10G and 10B via the signal lines 120A.

The scanning line driving circuit 130 includes shift registers and thelike which sequentially shift (transmit) a start pulse insynchronization with input clock pulses. The scanning line drivingcircuit 130 scans the respective scanning lines 130A with row units whenthe image signals are written in the respective light emitting portions10R, 10G and 10B, and sequentially supplies scanning signals to thescanning lines 130A.

The power supply line driving circuit 140 includes shift registers andthe like which sequentially shift (transmit) a start pulse insynchronization with input clock pulses. The power supply line drivingcircuit 140 appropriately supplies either of a first voltage and asecond voltage which are different from each other to the power supplylines 140A in synchronization with the scanning with row unit by thescanning line driving circuit 130. Thereby, a driving transistor Tr1described later is selectively switched between a conductive ornon-conductive state.

The pixel driving circuits 150 are provided on a layer (a pixel drivingcircuit forming layer 112 described later) between the substrate 111 andthe light emitting portions 10 (10R, 10G and 10B). FIG. 2 shows aconfiguration example of the pixel driving circuit 150. As shown in FIG.2, the pixel driving circuit 150 is an active type driving circuit whichincludes the driving transistor Tr1, a write transistor Tr2, a capacitor(storage capacitor) Cs therebetween, and the light emitting portion 10.Each of the light emitting portions 10R, 10G and 10B is connected inseries to the driving transistor Tr1 between the power supply line 140Aand a common power supply line GND. The driving transistor Tr1 and thewrite transistor Tr2 are constituted by a typical thin film transistor(TFT), and a configuration thereof is not particularly limited, and, forexample, may be a reverse stagger structure (a so called bottom gatetype) or may be a stagger structure (a top gate type).

The write transistor Tr2 has, for example, a drain electrode connectedto the signal line 120A and is supplied with an image signal from thesignal driving circuit 120. Also, the write transistor Tr2 has a gateelectrode connected to the scanning line 130A and is supplied with thescanning signal from the scanning line driving circuit 130. Further, asource electrode of the write transistor Tr2 is connected to a gateelectrode of the driving transistor Tr1.

The driving transistor Tr1 has, for example, a drain electrode connectedto the power supply line 140A and is set to either the first voltage orthe second voltage from the power supply line driving circuit 140. Asource electrode of the driving transistor Tr1 is connected to the lightemitting portion 10.

The storage capacitor Cs is formed between the gate electrode of thedriving transistor Tr1 (the source electrode of the write transistorTr2) and the source electrode of the driving transistor Tr1.

FIG. 3 shows a configuration example of the display region 110 extendedin the XY plane. Here, a planar configuration of the display region 110from which a second electrode layer 16, a protective layer 18, and asealing substrate 19 (which are all described later) are removed isshown in a plan view. In the display region 110, a plurality of lightemitting portions 10 is sequentially arranged in a matrix as a whole.More specifically, a metal layer 17 which is an auxiliary wire layer isdisposed in a reticular pattern, and, in each region divided by themetal layer 17, the light emitting portions 10 (10R, 10G and 10B)including emission regions 20 of which layouts are defined by anaperture defining insulation layer 24 are disposed one by one. Each ofthe emission regions 20 in the respective light emitting portions 10has, for example, a substantially rectangular shape having a long sidein the Y direction. The light emitting portion 10R of the organic lightemitting element 1R emits red light, the light emitting portion 10G ofthe organic light emitting element 1G emits green light, and the lightemitting portion 10B of the organic light emitting element 1B emits bluelight. Here, the organic light emitting elements 1 having the lightemitting portions 10 emitting the same colored light are arranged in oneline in the Y direction, and these are repeatedly disposed in the Xdirection in a constant order (for example, in an order of the organiclight emitting element 1R, the organic light emitting element 1G, andthe organic light emitting element 1B). Three organic light emittingelements 1R, 1G and 1B which are arranged in the X direction and aredifferent in emission colors constitute one pixel P. The period PTx ofthe pixels P ( . . . , P_(m,n−1), P_(m,n), P_(m,n+1), . . . ) arrangedin the X direction is longer than the period Pty of the pixels P ( . . ., P_(m−1,n), P_(m,n), P_(m+1,n), . . . ) arranged in the Y direction. Asshown in FIG. 3, apertures 24K are provided at the aperture defininginsulation layer 24 in some of the intersections of the metal layer 17.In the region included in each of the apertures 24K, a connectionportion 21 (a part surrounded by the broken line) for connecting themetal layer 17 to the second electrode layer 16 of the light emittingportion 10 is provided. Also, the number of the organic light emittingelements 1 (light emitting portions 10) arranged in the X and Ydirection are set arbitrarily, and thus is not limited to the numbershown in FIG. 3. Also, one pixel may include four or more organic lightemitting elements, or organic light emitting elements emitting whitelight may be provided.

A detailed configuration of the display region 110 will be describedwith reference to FIGS. 4 to 9.

FIGS. 4 to 6 respectively show cross-sectional configurations of theorganic light emitting elements 1R, 1G and 1B of the pixel 1 _(m,n) inthe display region 110. In other words, FIGS. 4, 5 and 6 respectivelyshow schematic configurations of XZ cross-sections taken along the linesIV-IV, V-V, and VI-VI shown in FIG. 3. As shown in each of FIGS. 4 to 6,in the display region 110, a light emitting portion forming layer 12including the light emitting portion 10 is formed on a base 11 in whicha pixel driving circuit forming layer 112 is provided on the substrate111. The protective layer 18 and the sealing substrate 19 aresequentially provided on the light emitting portion 10. The lightemitting portion 10 includes a first electrode layer 13 which is ananode electrode, an organic layer 14 including an emission layer 14C(described later), and a second electrode layer 16 which is a cathodeelectrode, which are sequentially laminated from the substrate 111 side.The organic layer 14 and the first electrode layer 13 are divided fromeach other by the aperture defining insulation layer 24 for each lightemitting portion 10. The second electrode layer 16 is provided in allthe light emitting portions 10. The metal layer 17 is covered by theaperture defining insulation layer 24 except for the regionscorresponding to the apertures 24K.

The aperture defining insulation layer 24 is provided to fill a gapbetween the first electrodes 13 and the organic layers 14 in theadjacent light emitting portions 10. The aperture defining insulationlayer 24 is made of, for example, an organic material such as polyimideor the like, secures insulation between the first electrode layer 13 andthe second electrode layer 16, and the metal layer 17, and accuratelydemarcates the emission region 20 of the light emitting portion 10.

The protective layer 18 covering the light emitting portion 10 is madeof an insulation layer such as silicon nitride (SiNx). The sealingsubstrate 19 formed thereon seals the light emitting portion 10 alongwith the protective layer 18, an adhesive layer (not shown) and thelike, and is made of a transparent material such as glass which enableslight generated from the emission layer 14C to be transmittedtherethrough.

Hereinafter, a detailed configuration of the base 11 and the organiclight emitting element 1 will be described. In addition, for the organiclight emitting elements 1R, 1G and 1B, except that the sterical shape(concavo-convex shape) of the first electrode layer 13, the organiclayer 14, and the second electrode layer 16, and materials forming theorganic layer 14 are partially different from each other, the remainingconfigurations are the same, and thus the description thereof will bemade together.

FIG. 7A is a schematic diagram illustrating a planar configuration ofthe pixel driving circuit 150 of the organic light emitting element 1Rprovided in the pixel driving circuit forming layer 112. Likewise, FIGS.7B and 7C are schematic diagrams illustrating planar configurations ofthe pixel driving circuits 150 of the organic light emitting elements 1Gand 1B. FIG. 4 shows a cross-section taken along the line IV-IV in FIG.7A. Also, FIGS. 5 and 6 show cross-sections taken along the lines V-Vand VI-VI in FIGS. 7B and 7C.

The base 11 is formed by providing the pixel driving circuit forminglayer 112 including the pixel driving circuit 150 on the substrate 111made of glass, silicon (Si) wafer, resin, or the like. On the surface ofthe substrate 111, as first metal layers, metal layers 211G which arethe gate electrodes of the driving transistors Tr1, metal layers 221Gwhich are the gate electrodes of the write transistors Tr2, and a partof the signal lines 120A (FIGS. 7A to 7C) are provided, respectively.The metal layers 211G, 221G and the signal lines 120A are covered by thegate insulation layers 212 made of silicon nitride, silicon oxide, orthe like.

For each of the driving transistors Tr1, a channel layer 213 formed of asemiconductor thin film such as amorphous silicon or the like isprovided in a part of the region corresponding to the metal layer 211Gon the gate insulation layer 212. An insulating channel protective layer214 is provided on the channel layer 213 so as to take up a channelregion 213R which is a central region, and the drain electrode 215D andthe source electrode 215S formed of an n type semiconductor thin filmsuch as n type amorphous silicon are provided at both regions thereof.The drain electrode 215D and the source electrode 215S are divided fromeach other by the channel protective layer 214, and the end surfacesthereof are spaced apart from each other with the channel region 213Rinterposed therebetween. As second metal layers, a metal layer 216Dwhich is a drain wire and a metal layer 216S which is a source wire areprovided to cover the drain electrode 215D and the source electrode215S, respectively. The metal layer 216D and the metal layer 216S have astructure where, for example, a titanium (Ti) layer, an aluminum (Al)layer, and a titanium layer are sequentially formed. The writetransistor Tr2 has the same configuration as the driving transistor Tr1.In FIGS. 7A to 7C, metal layers 221G as the first metal layers, andmetal layers 226D (drain wires) and metal layers 226S (source wiring) asthe second metal layers are shown as the constituent elements of thewrite transistor Tr2.

As the second metal layers, in addition to the above-described metallayers 216D, 226D, 216S and 226S, the scanning lines 130A and the powersupply lines 140A are provided. Here, although the driving transistorTr1 and the write transistor Tr2 having a reverse stagger structure (aso-called bottom gate type) are described, a stagger structure (aso-called top gate type) may be employed. In addition, the signal lines120A are formed as the second metal layers in regions other than theintersections of the scanning lines 130A and the power supply lines140A.

The pixel driving circuits 150 are entirely covered by protective layers(passivation layers) 217 made of silicon nitride or the like, and, alsoinsulating planarization layers 218 are provided thereon. Theplanarization layers 218 improve the planarity of the entire pixeldriving circuit forming layer 112. In addition, fine connection holes124 are provided in partial regions of the planarization layers 218 andthe protective layers 217 (see FIGS. 7A to 7C). The planarization layers218 particularly have the thickness larger than the protective layers217, and thus are preferably made of a material having good patternaccuracy, for example, such as an inorganic material including polyimideand the like. The connection holes 124 are filled with the firstelectrode layers 13 and electrically connected to the metal layers 216Sforming the source wires of the driving transistors Tr1.

The first electrode layers 13 formed on the planarization layers 218also function as reflection layers, and are preferably made of amaterial having as high reflectivity as possible from the viewpoint ofincreasing the luminous efficiency. For this reason, the first electrodelayers 13 are made of a material with high reflectivity such as aluminum(Al) or aluminum neodymium alloy (AlNd). Aluminum has low resistance toa developer used in a developing process when the apertures 24K of theaperture defining insulation layer 24 are formed and thus easilycorroded. In contrast, AlNd has high resistance to a developer and ishardly corroded. Therefore, the first electrode layers 13 are preferablyformed of a single layered structure made of AlNd or a double layeredstructure of an aluminum layer and AlNd (the Al layer (lower layer) andAlNd layer (upper layer)). Particularly, the double layered structure ofthe Al layer (lower layer) and the AlNd layer (upper layer) ispreferable due to having low resistance as compared with the singlelayered AlNd layer. The entire thickness of the first electrode layer 13ranges, for example, from 100 nm to 1000 nm. Also, if the firstelectrode layer 13 is formed of a double layered structured, the upperlayer thereof (contacting with the organic layer 14) may be made of theabove-described material having high reflectivity and the lower layerthereof (contacting with the planarization layer 218) may be made of amaterial having low reflectivity such as molybdenum (Mo) or compounds(alloys) thereof. In this way, the layer having high optical absorptanceis provided on the surface which contacts with the pixel driving circuitforming layer 112 provided with the driving transistor Tr1 and the writetransistor Tr2, and thereby it is possible to absorb unnecessary lightsuch as external light or light leaked from the light emitting portion10. Further, the first electrode layer 13 is formed to cover the surfaceof the planarization layer 218 and fills the connection hole 124, asdescribed above.

None of the first electrode layer 13, the organic layer 14, and thesecond electrode layer 16 forming the light emitting portions 10R, 10Gand 10B have horizontal surfaces but sterically undulating surfaceshapes including concave and convex. This is because as shown in thecross-sectional views in FIGS. 4 to 6, the surface of the pixel drivingcircuit forming layer 112 which underlies the light emitting portionforming layer 12 is not horizontal. That is to say, the stericalconcavo-convex shape is particularly caused by the metal layers formingthe driving transistor Tr1 and the write transistor Tr2, or the wirelayers such as the signal lines 120A, the scanning lines 130A, and thepower supply lines 140A, which are selectively provided on the substrate111. The difference in height is generated in the surface of the pixeldriving circuit forming layer 112 depending on the positions of thedisposed metal layers or wired layers, and, as a result, the firstelectrode layer 13, the organic layer 14, and the second electrode layer16 also have the difference in height in the XY plane depending on theirpositions.

In this example embodiment, positions of disposed metal layers and wiredlayers corresponding to the respective organic light emitting elements1R, 1G and 1B in each pixel P or planar shapes thereof are differentfrom each other. Specifically, the planar shapes thereof are differentby changing positions or sizes of grooves or apertures in the metallayers 211G and 216S, in the organic light emitting elements 1R, 1G and1B. Thereby, the organic light emitting elements 1R, 1G and 1B formingone pixel P are different from each other in undulation (stericalconcavo-convex shape) of the layer surfaces of the light emittingportions 10R, 10G and 10B.

In this example embodiment, the light emitting portions 10 of a certainpixel (for example, the pixel P_(m,n)) preferably have layer surfacesdifferent from the light emitting portions 10 of other pixels adjacentthereto (for example, P_(m+1,n), P_(m−1,n), P_(m,n+1), and P_(m,n−1)).In this case, the light emitting portions 10 of the pixels P which areadjacent to each other at least in the X direction, and further thelight emitting portions 10 of the pixels P which are adjacent to eachother in the X and Y directions more preferably have undulating layersurfaces different from each other. In addition, in the display region110, a plurality of light emitting portions 10 having undulation of thesame layer surface shape is preferably arranged at an irregular intervalin at least one direction of the X direction and the Y direction.Particularly, most preferably, in the display region 110 all of thelight emitting portions 10 of the pixels P have undulating layersurfaces different from each other.

The organic layer 14 is entirely formed in the emission region 20demarcated by the aperture defining insulation layer 24 with no gaps.The organic layer 14, for example, as shown in FIG. 8, has aconfiguration where a hole injection layer 14A, a hole transfer layer14B, the emission layer 14C, and an electron transfer layer 14D aresequentially laminated from the first electrode layer 13 side. Thelayers other than the emission layer 14C may be optionally formed. FIG.8 shows the cross-section of the organic layer 14 through partialenlargement.

The hole injection layer 14A is a buffer layer for increasing holeinjection efficiency and preventing leakage. The hole transfer layer 14Bincreases efficiency of transferring holes to the emission layer 14C. Inthe emission layer 14C, electrons and holes are recombined byapplication of an electric field and thus light is generated. Theelectron transfer layer 14D increases efficiency of transferringelectrons to the emission layer 14C. An electron injection layer (notshown) made of LiF, Li₂O, or the like may be formed between the electrontransfer layer 14D and the second electrode layer 16.

In addition, the organic layers 14 have different configurationsdepending on the emission colors of the light emitting portions 10R, 10Gand 10B. The hole injection layer 14A of the light emitting portion 10Rhas the thickness of, for example, 5 nm or more to 300 nm or less and ismade of 4,4′,4″-tris(3-methylphenyl phenylamino), triphenylamino(m-MTDATA) or 4,4′,4″-tris(2-naphthylphenylamino) (2-TNATA). The holetransfer layer 14B of the light emitting portion 10R has the thicknessof, for example, 5 nm or more to 300 nm or less, and is made ofbis[(N-naphtyl)-N-phenyl]benzidine (α-NPD). The emission layer 14C ofthe light emitting portion 10R has the thickness of, for example, 10 nmor more to 100 nm or less, and is made of a mixture of(tris(8-hydoxyquinoline)-aluminum (Alq₃) and2,6-bis[4-[N-(4-methoxylphenyl)-N-phenyl]aminostyryl]naphthalene-1,5-dicarbonitrile(BSN-BCN) of 40% by volume. The electron transfer layer 14D of the lightemitting portion 10R has the thickness of, for example, 5 nm or more to300 nm or less, and is made of Alq₃.

The hole injection layer 14A of the light emitting portion 10G has thethickness of, for example, 5 nm or more to 300 nm or less and is made ofm-MTDATA or 2-TNATA. The hole transfer layer 14B of the light emittingportion 10G has the thickness of, for example, 5 nm or more to 300 nm orless, and is made of α-NPD. The emission layer 14C of the light emittingportion 10G has the thickness of, for example, 10 nm or more to 100 nmor less, and is made of a mixture of Alq₃ and Coumarin6 of 3% by volume.The electron transfer layer 14D of the light emitting portion 10G hasthe thickness of, for example, 5 nm or more to 300 nm or less, and ismade of Alq₃.

The hole injection layer 14A of the light emitting portion 10B has thethickness of, for example, 5 nm or more to 300 nm or less and is made ofm-MTDATA or 2-TNATA. The hole transfer layer 14B of the light emittingportion 10B has the thickness of, for example, 5 nm or more to 300 nm orless, and is made of α-NPD. The emission layer 14C of the light emittingportion 10B has the thickness of, for example, 10 nm or more to 100 nmor less, and is made of spiro6φ. The electron transfer layer 14D of thelight emitting portion 10B has the thickness of, for example, 5 nm ormore to 300 nm or less, and is made of Alq₃.

The second electrode layer 16 has the thickness of, for example, 5 nm ormore to 50 nm or less, and is made of a simple substance such asaluminum (Al), magnesium (Mg), calcium (Ca), sodium (Na) an alloythereof or the like. Among them, an alloy of magnesium and silver (MgAgalloy), or an alloy of aluminum (Al) and lithium (Li) (AlLi alloy) ispreferable. The second electrode layer 16 is commonly provided in allthe light emitting portions 10R, 10G and 10B and is disposed opposite tothe first electrode layer 13 of each of the light emitting portions 10R,10G and 10B. Further, the second electrode layer 16 is formed to coverthe aperture defining insulation layer 24 as well as the organic layer14.

FIG. 9 shows the cross-section of the vicinity of the connection portion21 shown in FIG. 3 through enlargement. The metal layer 17 is formed onthe surface of the planarization layer 218 in the same manner as thefirst electrode layer 13 and functions as an auxiliary wire whichsupplements voltage drop at the second electrode layer 16. As describedabove, the metal layer 17 is covered by the second electrode layer 16 inthe connection portion 21 inside the region of the aperture 24K, and iselectrically connected to the second electrode layer 16 (see FIG. 10).

If the metal layer 17 does not exist, due to the voltage drop accordingto the distance between a power supply (not shown) and the respectivelight emitting portions 10R, 10G and 10B, potentials at the secondelectrode layer 16 connected to the common power supply line GND (seeFIG. 2) are not constant in the respective light emitting portions 10R,10G and 10B but have notable differences. The difference in thepotentials at the second electrode layer 16 result in uneven luminancein the display region 110, and thus it is not preferable. The metallayer 17 suppresses the voltage drop from the power supply to the secondelectrode layer 16 to the minimum and functions to suppress the unevenluminance, even when the display device has a large size.

The display device can be manufactured as follows. Hereinafter, amanufacturing method of the display device in this example embodimentwill be described with reference to FIGS. 4 to 7.

First, the pixel driving circuit 150 including the driving transistorTr1 and the write transistor Tr2 is formed on the substrate 111 made ofthe above-described material. Specifically, first, a metal layer isformed on the substrate 111 by, for example, sputtering. Thereafter, themetal layers 211G and 221G and a part of the signal lines 120A areformed on the substrate 111 by patterning the metal layer by, forexample, a photolithography method, a dry etching, or a wet etching.Next, the entire surface is covered by the gate insulation layer 212.Further, on the gate insulation layer 212, the channel layer, thechannel protective layer, the drain electrode, the source electrode, andthe metal layers 216D and 226D, and the metal layers 216S and the 226Sare sequentially formed to have predetermined shapes, respectively.Here, a part of the signal lines 120A, and the scanning lines 130A andthe power supply lines 140A are respectively formed as the second metallayers when the metal layers 216D and 226D and the metal layers 216S and226S are formed. At this time, connection portions connecting the metallayer 221G to the scanning lines 130A, connection portions connectingthe metal layer 226D to the signal lines 120A, and connection portionsconnecting the metal layer 226S to the metal layer 211G are formed inadvance. Thereafter, the entire surface is covered by the protectivelayer 217 to complete the pixel driving circuit 150. At this time, theapertures are formed at predetermined positions on the metal layer 216Sin the protective layer 217 by a dry etching or the like.

After the pixel driving circuits 150 are formed, a photosensitive resinusing, for example, polyimide as a main component is coated on theentire surface by a spin coating method or the like. Next, aphotolithography process is performed for the photosensitive resin,thereby forming the planarization layer 218 having the connection holes124. Specifically, for example, through selective exposure anddevelopment using a mask having apertures at predetermined positions,the connection holes 124 which are connected to the apertures providedin the protective layer 217 are formed. Thereafter, the planarizationlayer 218 may be optionally fired. Thereby, the pixel driving circuitforming layer 112 is obtained.

Also, the first electrode layer 13 and the metal layer 17 made of theabove-described materials are formed. Specifically, for example, themetal layer made of the above-described material is formed on the entiresurface by, for example sputtering, a resist pattern (not shown) havinga predetermined shape is formed on the laminated layer using a certainmask. Further, the metal layer is selectively etched using the resistpattern as a mask. At this time, the first electrode layer 13 is formedto cover the surface of the planarization layer 218 and fill theconnection holes 124. In addition, the metal layer 17 is formed tosurround the periphery of the first electrode layer 13 and not tooverlap with the signal lines 120A on the surface of the planarizationlayer 218. The metal layer 17 is preferably formed along with the firstelectrode layer 13 using the same material as the first electrode layer13.

Then, the aperture defining insulation layer 24 is formed to fill a gapbetween the first electrode layers 13 which are adjacent to each otherand to cover the metal layer 17. At this time, the apertures 24K areformed at predetermined positions.

Next, in order to completely cover the exposed parts of the firstelectrode layer 13, the hole injection layer 14A, the hole transferlayer 14B, and the emission layer 14C, and the electron transfer layer14D, which are made of the above-described predetermined materials andhave the above-described thicknesses, are sequentially laminated by, forexample, a deposition method, thereby forming the organic layer 14.Further, the second electrode layer 16 covers the organic layer 14 so asto be opposite to the first electrode layer 13 with the organic layer 14interposed therebetween, and is formed to entirely cover the metal layer17 in the connection portion 21, thereby forming the organic lightemitting element 1.

The protective layer 18 is formed to cover the entire surface. Finally,the adhesive layer is formed on the protective layer 18, and the sealingsubstrate 19 is attached to the protective layer 18 via the adhesivelayer. In this way, the display device is completed.

In the display device manufactured in this way, the scanning signal issupplied to each pixel from the scanning line driving circuit 130 viathe gate electrode (the metal layer 221G) of the write transistor Tr2,and the image signal from the signal driving circuit 120 is stored inthe storage capacitor Cs via the write transistor Tr2. The power supplyline driving circuit 140 supplies the first voltage higher than thesecond voltage to each power supply line 140A in synchronization withthe scanning with row units by the scanning line driving circuit 130.Thereby, the conductive state of the driving transistor Tr1 is selectedto cause a driving current Id to be injected into each of the lightemitting portions 10R, 10G and 10B, and thus holes and electrons arerecombined to emit light. This light is multiply reflected between thefirst electrode layer 13 and the second electrode layer 16, istransmitted through the second electrode layer 16, the protective layer18, and the sealing substrate 19, and is emitted outwards.

As described above, in this example embodiment, in an arbitrary pixel P,the positions of the arranged metal layers and wired layers, which formthe pixel driving circuits 150 of the organic light emitting elements1R, 1G and 1B, or the planar shapes thereof are different from eachother. Thereby, the undulations (sterical concavo-convex shapes) on thelayer surfaces of the light emitting portions 10R, 10G and 10B in thepixel P can be different from each other. For this reason, even whenexternal light is incident, angles of the external light which isreflected from the layer surfaces of the light emitting portions 10R,10G and 10B (particularly, the layer surfaces of the organic layers 14)are different from each other, and thus it is possible to suppress theinterference of the reflected external light and decrease the intensitythereof. As a result, by means of the display device, it is possible toreduce generation of unnecessary light which hinders the recognition oforiginal display images, and to secure better image display performance,even when the thickness of the planarization layer 218 is not increasedand the entire configuration becomes thin.

In this example embodiment, in the case where the light emittingportions 10 of an arbitrary pixel P have undulating layer surfacesdifferent from the light emitting portions 10 of other pixels adjacentthereto, it is possible to further reduce the interference and theintensity of the reflected external light. Also, if the interference andthe intensity of the reflected external light are to be reduced, it iseffective that the light emitting portions 10 including the organiclayers 14 having the undulation of the same layer surface shape areirregularly arranged in at least one of the X direction the Y direction.Particularly, it is ideal and most preferable that the light emittingportions 10 of all the pixels P in the display region 110 have stericalshapes different from each other. However, if the light emittingportions 10 of the pixels P adjacent to each other in the X directionhave undulating layer surfaces different from each other, it is possibleto secure good image display performance to the extent of causing noinconvenience when practically used.

In addition, one display region 110 includes a plurality of dividedareas, and the light emitting portions 10 having undulation of the samelayer surfaces may be irregularly arranged in each divided area. In thiscase, the irregular arrangement patterns of the light emitting portions10 in the plural divided areas may correspond with each other. In thiscase, for example, when the metal layers 211G and 216S are patterned,the same hard mask having a predetermined pattern shape is repeatedlyused, and thus ease of manufacturing is improved.

In the above description, although the present disclosure has beendescribed using the example embodiment, the present disclosure is notlimited to the example embodiment but may have various modifications.For example, in the above-described example embodiment, although thecase where all of the first electrode layer 13, the organic layer 14,and the second electrode layer 16 in the light emitting portions 10adjacent to each other have undulating layer surfaces different fromeach other has been described, the present disclosure is not limitedthereto. The organic layers 14 in which more reflected external lightoccurs may have undulations different from each other.

In addition, when the undulation of the layer surface shape of theorganic layer is changed, for example, as shown in FIGS. 10A to 10C,only positions of apertures of constituent elements (specifically, themetal layers 211G and 216S) of the pixel driving circuit forming layer112 which is a base of the light emitting portion 10 may be changed.Alternatively, for example, as shown in FIGS. 11A to 11C, only the sizesand the shapes of the apertures may be changed. Further, for example, asshown in FIGS. 12A and 12B, an isolated interposition layer DP may beprovided independently from the constituent elements of the pixeldriving circuit 150 such as the metal layers 211G and 216S. In addition,for example, as shown in FIG. 12C, shapes (for example, a partial shapeof the power supply line 140A) of constituent elements other than thedriving elements may be changed. In addition, the combination of theshapes, the sizes and the positions of the respective constituentelements of the pixel driving circuit forming layer 112 shown in FIGS.7, and 10A to 12C are only an example, and the present disclosure is notlimited thereto. As long as the undulation of the surface shape of thepixel driving circuit forming layer 112 is changed, the undulation ofthe layer surface shape of the light emitting portion 10 may be changed.

The present disclosure is not limited to the materials for therespective layers, the laminating order, or the layer forming methodsdescribed in the above-described example embodiment. For example, in theexample embodiment, although the case where the first electrode layer 13is an anode and the second electrode layer 16 is a cathode has beendescribed, the first electrode layer 13 may be a cathode and the secondelectrode layer 16 may be an anode. Further, in the example embodiment,although the detailed configurations of the light emitting portions 10R,10G and 10B have been all described, it is not necessary for all thelayers to be provided but another layer may be provided. For example, ahole injection thin film layer made of chromium oxide (III) (Cr₂O₃), ITO(Indium Tin Oxide: an oxide film of mixture of indium (In) and tin(Sn)), or the like may be formed between the first electrode layer 13and the organic layer 14.

In addition, in the example embodiment, although the case where thesecond electrode layer 16 is formed of the transflective reflectionlayer has been described, the second electrode layer 16 may have astructure where the transflective reflection layer and a transparentelectrode are sequentially laminated from the first electrode layer 13side. The transparent electrode decreases electric resistance of thetransflective reflection layer, and is made of a conductive materialwhich allows light generated from the emission layer to be sufficientlytransmitted therethrough. As a material forming the transparentelectrode, for example, ITO or a compound including indium, zinc (Zn),and oxygen is preferable. This is because good conductivity is obtainedeven when a film is formed at room temperature. The thickness of thetransparent electrode may be, for example, from 30 nm to 1000 nm. Also,in this case, a resonator structure may be formed in which thetransflective layer is one end, the other end is formed at a positionopposite to the transflective electrode with the transparent electrodeinterposed therebetween, and the transparent electrode is a resonantportion. Further, after the resonator structure is formed, the lightemitting portions 10R, 10G and 10B are covered by the protective layer18, and if the protective layer 18 is made of a material having almostthe same refractive index as the material forming the transparentelectrode, the protective layer 18 can be formed as a part of theresonant portion, which is preferable.

In addition, in the example embodiments, although the case of the activematrix type display device has been described, the present disclosure isapplicable to passive matrix type display devices. Further, theconfigurations of the pixel driving circuits for the active matrixdriving are not limited to ones described in the example embodiments,but capacitive elements or transistors may be added if necessary. Inthis case, necessary driving circuits may be added in addition to theabove-described signal driving circuit 120 and scanning line drivingcircuit 130.

It should be understood that various changes and modifications to thepresently preferred example embodiments described herein will beapparent to those skilled in the art. Such changes and modifications canbe made without departing from the spirit and scope and withoutdiminishing its intended advantages. It is therefore intended that suchchanges and modifications be covered by the appended claims.

The application is claimed as follows:
 1. A display device comprising: acircuit layer including: a plurality of transistors; a plurality ofmetal layers; and a plurality of wirings, and a display layer overlyingthe circuit layer, the display layer including: a first light emittingelement configured to emit light of a first color; a second lightemitting element configured to emit light of a second color; and a thirdlight emitting element configured to emit light of a third color,wherein (a) the first light emitting element includes a first anodeelectrode and a first light emitting layer disposed on the first anodeelectrode, a surface of the first anode electrode having a first surfacecontour structure; (b) the second light emitting element includes asecond anode electrode and a second light emitting layer disposed on thesecond anode electrode, a surface of the second anode electrode having asecond surface contour structure which is different from the firstsurface contour structure; and (c) the third light emitting elementincludes a third anode electrode and a third light emitting layerdisposed on the third anode electrode, a surface of the third anodeelectrode having a third surface contour structure which is differentfrom the second surface contour structure.
 2. The display device ofclaim 1, wherein: (a) a first portion of the circuit layer correspondingto a first region under the first light emitting element has a firstpattern; (b) a second portion of the circuit layer corresponding to asecond region under the second light emitting element has a secondpattern which is different from the first pattern; and (c) a thirdportion of the circuit layer corresponding to a third region under thethird light emitting element has a third pattern which is different fromthe second pattern, and wherein each of the first, the second and thethird surface contour structures is respectively based on the first, thesecond and the third patterns of the circuit layer.
 3. The displaydevice of claim 2, wherein: the second pattern is different from thefirst pattern in a first direction; and the third pattern is differentfrom the second pattern in the first direction.
 4. The display device ofclaim 3, wherein: the second pattern is different from the first patternin both of the first direction and a second direction which isperpendicular to the first direction; and the third pattern is differentfrom the second pattern in both of the first direction and the seconddirection.
 5. The display device of claim 2, wherein: the first portionof the circuit layer includes a first transistor disposed on a firstlocation within the first region; the second portion of the circuitlayer includes a second transistor disposed on a second location withinthe second region, the second location being different within the secondregion relative to the first location within the first region; and thethird portion of the circuit layer includes a third transistor disposedon a third location within the third region, the third location beingdifferent within the third region relative to the second location withinthe second region.
 6. The display device of claim 5, wherein: the firsttransistor is configured to drive the first light emitting element; thesecond transistor is configured to drive the second light emittingelement; and the third transistor is configured to drive the third lightemitting element.
 7. The display device of claim 2, wherein the wiringsincludes first, second and third wirings respectively extending in thefirst, the second and the third regions, and wherein one of the first,the second and the third wirings has a protrusion within a correspondingone of the first, the second and the third regions.
 8. The displaydevice of claim 7, wherein another one of the first, the second and thethird wirings does not have a protrusion within a corresponding one ofthe first, the second and the third regions.
 9. The display device ofclaim 7, wherein only one of the first, the second and the third wiringshas the protrusion within a corresponding one of the first, the secondand the third regions.
 10. The display device of claim 2, wherein: thefirst portion of the circuit layer includes a first metal layer having afirst pattern; the second portion of the circuit layer includes a secondmetal layer having a second pattern which is different from the firstpattern; the third portion of the circuit layer includes a third metallayer having a third pattern which is different from the second pattern.11. The display device of claim 10, wherein: each of the first, thesecond and the third patterns respectively has a feature selected from agroup consisting of an opening, a notch, an island shape and acombination thereof.
 12. The display device of claim 1, wherein thefirst color is red, the second color is green and the third color isblue.
 13. The display device of claim 1, wherein the first lightemitting element, the second light emitting element and the third lightemitting element are aligned in a first direction.
 14. The displaydevice of claim 1, wherein: (a) the first light emitting elementincludes a first cathode electrode disposed on the first light emittinglayer, a surface of the first cathode electrode having a first cathodesurface contour structure; (b) the second light emitting elementincludes a second cathode electrode disposed on the second lightemitting layer, a surface of the second cathode electrode having asecond cathode surface contour structure which is different from thefirst cathode surface contour structure; and (c) the third lightemitting element includes a third cathode electrode disposed on thethird light emitting layer, a surface of the third cathode electrodehaving a third cathode surface contour structure which is different fromthe second cathode surface contour structure.
 15. The display device ofclaim 14, wherein: (a) a first portion of the circuit layercorresponding to a first region under the first light emitting elementhas a first pattern; (b) a second portion of the circuit layercorresponding to a second region under the second light emitting elementhas a second pattern which is different from the first pattern; and (c)a third portion of the circuit layer corresponding to a third regionunder the third light emitting element has a third pattern which isdifferent from the second pattern, and wherein each of the first, thesecond and the third cathode surface contour structures is respectivelybased on the first, the second and the third patterns of the circuitlayer.
 16. The display device of claim 14, wherein the first, the secondand the third cathode are formed as a common layer.
 17. The displaydevice of claim 1, wherein: the first surface contour structure has afirst convex shape when viewed as a cross-section; the second surfacecontour structure has a second convex shape which is different from thefirst convex shape when viewed as a cross-section; and the third surfacecontour structure has a third convex shape which is different from thesecond convex shape when viewed as a cross-section.
 18. The displaydevice of claim 1, wherein: the first surface structure has a firstconcave shape when viewed as a cross-section; the second surfacestructure has a second concave shape which is different from the firstconcave shape when viewed as a cross-section; and the third surfacestructure has a third concave shape which is different from the secondconcave shape when viewed as a cross-section.
 19. The display device ofclaim 1, wherein the third surface contour structure is different fromboth of the first surface contour structure and the second surfacecontour structure.
 20. The display device of claim 2, wherein thecircuit layer includes a planarization layer overlying the transistors,metal layers and the wirings; and wherein each of the first, the secondand the third patterns is respectively reflected into the first, thesecond and the third surface contour structures via the planarizationlayer.
 21. A display device comprising: a circuit layer including: aplurality of transistors; a plurality of metal layers; and a pluralityof wirings, and a display layer overlying the circuit layer, the displaylayer including: a first light emitting element configured to emit lightof a first color; a second light emitting element configured to emitlight of a second color; and a third light emitting element configuredto emit light of a third color, wherein (a) a first portion of thecircuit layer corresponding to a first region under the first lightemitting element has a first pattern; (b) a second portion of thecircuit layer corresponding to a second region under the second lightemitting element has a second pattern which is different from the firstpattern; and (c) a third portion of the circuit layer corresponding to athird region under the third light emitting element has a third patternwhich is different from the second pattern.
 22. The display device ofclaim 21, wherein: the second pattern is different from the firstpattern in a first direction; and the third pattern is different fromthe second pattern in the first direction.
 23. The display device ofclaim 22, wherein: the second pattern is different from the firstpattern in both of the first direction and a second direction which isperpendicular to the first direction; and the third pattern is differentfrom the second pattern in both of the first direction and the seconddirection.
 24. The display device of claim 21, wherein: the firstportion of the circuit layer includes a first transistor disposed on afirst location within the first region; the second portion of thecircuit layer includes a second transistor disposed on a second locationwithin the second region, the second location being different within thesecond region relative to the first location within the first region;and the third portion of the circuit layer includes a third transistordisposed on a third location within the third region, the third locationbeing different within the third region relative to the second locationwithin the second region.
 25. The display device of claim 21, whereinthe wirings includes first, second and third wirings respectivelyextending in the first, the second and the third regions, and whereinone of the first, the second and the third wirings has a protrusionwithin a corresponding one of the first, the second and the thirdregions.
 26. The display device of claim 25, wherein only one of thefirst, the second and the third wirings has the protrusion within acorresponding one of the first, the second and the third regions.
 27. Anelectronic device comprising a circuit layer and a light emission layer,the light emission layer including: a first light emitting elementconfigured to emit light of a first color; a second light emittingelement configured to emit light of a second color; and a third lightemitting element configured to emit light of a third color, wherein (a)the first light emitting element includes a first anode electrode and afirst light emitting layer on the first anode electrode, a surface ofthe first anode electrode having a first surface contour structure; (b)the second light emitting element includes a second anode electrode anda second light emitting layer on the second anode electrode, a surfaceof the second anode electrode having a second surface contour structurewhich is different from the first surface contour structure; and (c) thethird light emitting element includes a third anode electrode and athird light emitting layer on the third anode electrode, a surface ofthe third anode electrode having a third surface contour structure whichis different from the second surface contour structure.
 28. Theelectronic device of claim 27, wherein the first color is red, thesecond color is green and the third color is blue.
 29. The electronicdevice of claim 27, wherein the first light emitting element, the secondlight emitting element and the third light emitting element are alignedin a first direction.
 30. The electronic device of claim 27, wherein theelectronic device is a passive-matrix type display device.